“…Madeira et al 59 investigated the content of gunshot residues with a wavelength dispersive analysis technique, making use of the WD-XRF sequential analyzer instrument model XRF-1800 (Shimadzu, Japan). The instrument housed a 4 kW Rh target X-ray tube, with a maximum voltage of 30 kV, a maximum current of 150 mA, a pendulum-type sample loading system, 10 different crystals, 3 slits, a FPC and a SC, and 5 primary X-ray filters and had the possibility to change the aperture.…”